<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="UTF-8" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <title>Document</title>
    <style>
      .outer {
        width: 400px;
        /* background-color: #cecece; */
        /* clear: both; */
      }
      .outer > div {
        float: left;
        border-width: 50px;
        border-style: solid;
        border-color: transparent;
      }
      .outer > div:nth-of-type(3) {
        border-bottom-color: blue;
        border-left-color: blue;
      }
      .outer > div:nth-of-type(5) {
        border-right-color: rgb(255, 102, 0);
        border-bottom-color: rgb(255, 102, 0);
      }
      .outer > div:nth-of-type(6) {
        border-color: rgb(255, 102, 0);
      }
      .outer > div:nth-of-type(7) {
        border-color: blue;
      }
      .outer > div:nth-of-type(10) {
        border-color: yellow;
      }
      .outer > div:nth-of-type(11) {
        border-color: greenyellow;
      }
      .outer > div:nth-of-type(12) {
        border-top-color: greenyellow;
        border-left-color: greenyellow;
      }
      .outer > div:nth-of-type(14) {
        border-top-color: yellow;
        border-right-color: yellow;
      }
    </style>
  </head>
  <body>
    <div class="outer">
      <div></div>
      <div></div>
      <div></div>
      <div></div>
      <div></div>
      <div></div>
      <div></div>
      <div></div>
      <div></div>
      <div></div>
      <div></div>
      <div></div>
      <div></div>
      <div></div>
      <div></div>
      <div></div>
    </div>
  </body>
</html>
